An exhaust purification device is known which includes an exhaust pipe member that forms an exhaust path through which exhaust from an internal combustion engine flows, and a particulate matter collection part that is provided in the exhaust path formed by the exhaust pipe member and collects a particulate matter contained in the exhaust (refer to Patent Document 1). A high-frequency irradiation part irradiates the particulate matter collection part with high-frequency waves. Movable reflection parts are provided on the upstream side and the downstream side, respectively, across the particulate matter collection part in a direction of flow of the exhaust in the exhaust path. Further, the movable reflection parts reflect the high-frequency waves radiated from the high-frequency irradiation part toward the particulate matter collection part, and at least one of the movable reflection parts on the upstream side and the downstream side has a reflection surface which reflects the high-frequency waves to the particulate matter collecting part and is movable with respect to the particulate matter collection part.
Besides, an internal combustion engine filter regenerative apparatus is known which includes an exhaust pipe that discharges exhaust gas from an internal combustion engine and a filter that is housed in the exhaust pipe and collects particulates contained in the exhaust gas (refer to Patent Document 2). A filter regenerator heats and burns the particulates. A temperature detector detects the temperature of the filter. A control unit controls the operation time of the filter regenerator on the basis of a signal from the temperature detector.
Patent Document 1: Japanese Laid-open Patent Publication No. 2011-163341
Patent Document 2: Japanese Laid-open Patent Publication No. H5-202733
There is a problem in irradiating the particulate matter collection part with high-frequency waves, in which unevenness occurs in a temperature distribution in the particulate matter collection part to make it difficult to uniformly remove the particulate matter in the particulate matter collection part, thereby failing to remove the particulate matter in a region at low temperature. Further, a local temperature rise may melt and break a part of the particulate matter collection part.